1 /* DDG - Data Dependence Graph - interface. 2 Copyright (C) 2004-2013 Free Software Foundation, Inc. 3 Contributed by Ayal Zaks and Mustafa Hagog <zaks,mustafa@il.ibm.com> 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it under 8 the terms of the GNU General Public License as published by the Free 9 Software Foundation; either version 3, or (at your option) any later 10 version. 11 12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 #ifndef GCC_DDG_H 22 #define GCC_DDG_H 23 24 /* For sbitmap. */ 25 #include "sbitmap.h" 26 /* For basic_block. */ 27 #include "basic-block.h" 28 #include "df.h" 29 30 typedef struct ddg_node *ddg_node_ptr; 31 typedef struct ddg_edge *ddg_edge_ptr; 32 typedef struct ddg *ddg_ptr; 33 typedef struct ddg_scc *ddg_scc_ptr; 34 typedef struct ddg_all_sccs *ddg_all_sccs_ptr; 35 36 typedef enum {TRUE_DEP, OUTPUT_DEP, ANTI_DEP} dep_type; 37 typedef enum {REG_OR_MEM_DEP, REG_DEP, MEM_DEP, REG_AND_MEM_DEP} 38 dep_data_type; 39 40 /* The following two macros enables direct access to the successors and 41 predecessors bitmaps held in each ddg_node. Do not make changes to 42 these bitmaps, unless you want to change the DDG. */ 43 #define NODE_SUCCESSORS(x) ((x)->successors) 44 #define NODE_PREDECESSORS(x) ((x)->predecessors) 45 46 /* A structure that represents a node in the DDG. */ 47 struct ddg_node 48 { 49 /* Each node has a unique CUID index. These indices increase monotonically 50 (according to the order of the corresponding INSN in the BB), starting 51 from 0 with no gaps. */ 52 int cuid; 53 54 /* The insn represented by the node. */ 55 rtx insn; 56 57 /* A note preceding INSN (or INSN itself), such that all insns linked 58 from FIRST_NOTE until INSN (inclusive of both) are moved together 59 when reordering the insns. This takes care of notes that should 60 continue to precede INSN. */ 61 rtx first_note; 62 63 /* Incoming and outgoing dependency edges. */ 64 ddg_edge_ptr in; 65 ddg_edge_ptr out; 66 67 /* Each bit corresponds to a ddg_node according to its cuid, and is 68 set iff the node is a successor/predecessor of "this" node. */ 69 sbitmap successors; 70 sbitmap predecessors; 71 72 /* For general use by algorithms manipulating the ddg. */ 73 union { 74 int count; 75 void *info; 76 } aux; 77 }; 78 79 /* A structure that represents an edge in the DDG. */ 80 struct ddg_edge 81 { 82 /* The source and destination nodes of the dependency edge. */ 83 ddg_node_ptr src; 84 ddg_node_ptr dest; 85 86 /* TRUE, OUTPUT or ANTI dependency. */ 87 dep_type type; 88 89 /* REG or MEM dependency. */ 90 dep_data_type data_type; 91 92 /* Latency of the dependency. */ 93 int latency; 94 95 /* The distance: number of loop iterations the dependency crosses. */ 96 int distance; 97 98 /* The following two fields are used to form a linked list of the in/out 99 going edges to/from each node. */ 100 ddg_edge_ptr next_in; 101 ddg_edge_ptr next_out; 102 103 /* For general use by algorithms manipulating the ddg. */ 104 union { 105 int count; 106 void *info; 107 } aux; 108 }; 109 110 /* This structure holds the Data Dependence Graph for a basic block. */ 111 struct ddg 112 { 113 /* The basic block for which this DDG is built. */ 114 basic_block bb; 115 116 /* Number of instructions in the basic block. */ 117 int num_nodes; 118 119 /* Number of load/store instructions in the BB - statistics. */ 120 int num_loads; 121 int num_stores; 122 123 /* Number of debug instructions in the BB. */ 124 int num_debug; 125 126 /* This array holds the nodes in the graph; it is indexed by the node 127 cuid, which follows the order of the instructions in the BB. */ 128 ddg_node_ptr nodes; 129 130 /* The branch closing the loop. */ 131 ddg_node_ptr closing_branch; 132 133 /* Build dependence edges for closing_branch, when set. In certain cases, 134 the closing branch can be dealt with separately from the insns of the 135 loop, and then no such deps are needed. */ 136 int closing_branch_deps; 137 138 /* Array and number of backarcs (edges with distance > 0) in the DDG. */ 139 int num_backarcs; 140 ddg_edge_ptr *backarcs; 141 }; 142 143 144 /* Holds information on an SCC (Strongly Connected Component) of the DDG. */ 145 struct ddg_scc 146 { 147 /* A bitmap that represents the nodes of the DDG that are in the SCC. */ 148 sbitmap nodes; 149 150 /* Array and number of backarcs (edges with distance > 0) in the SCC. */ 151 ddg_edge_ptr *backarcs; 152 int num_backarcs; 153 154 /* The maximum of (total_latency/total_distance) over all cycles in SCC. */ 155 int recurrence_length; 156 }; 157 158 /* This structure holds the SCCs of the DDG. */ 159 struct ddg_all_sccs 160 { 161 /* Array that holds the SCCs in the DDG, and their number. */ 162 ddg_scc_ptr *sccs; 163 int num_sccs; 164 165 ddg_ptr ddg; 166 }; 167 168 169 ddg_ptr create_ddg (basic_block, int closing_branch_deps); 170 void free_ddg (ddg_ptr); 171 172 void print_ddg (FILE *, ddg_ptr); 173 void vcg_print_ddg (FILE *, ddg_ptr); 174 void print_ddg_edge (FILE *, ddg_edge_ptr); 175 void print_sccs (FILE *, ddg_all_sccs_ptr, ddg_ptr); 176 177 ddg_node_ptr get_node_of_insn (ddg_ptr, rtx); 178 179 void find_successors (sbitmap result, ddg_ptr, sbitmap); 180 void find_predecessors (sbitmap result, ddg_ptr, sbitmap); 181 182 ddg_all_sccs_ptr create_ddg_all_sccs (ddg_ptr); 183 void free_ddg_all_sccs (ddg_all_sccs_ptr); 184 185 int find_nodes_on_paths (sbitmap result, ddg_ptr, sbitmap from, sbitmap to); 186 int longest_simple_path (ddg_ptr, int from, int to, sbitmap via); 187 188 bool autoinc_var_is_used_p (rtx, rtx); 189 190 #endif /* GCC_DDG_H */ 191